xxtea_java.rar_XXTEA_XXTEA java_java XXTEA_java加解密

/* xencrypt.java */ public class xencrypt { private xencrypt() {} /** * Encrypt data with key. * * @param data * @param key * @return */ public static byte[] encrypt(byte[] data, byte[] key) { if (data.length == 0) { return data; } return toByteArray( encrypt(toIntArray(data, true), toIntArray(key, false)), false); } /** * Decrypt data with key. * * @param data * @param key * @return */ public static byte[] decrypt(byte[] data, byte[] key) { if (data.length == 0) { return data; } return toByteArray( decrypt(toIntArray(data, false), toIntArray(key, false)), true); } /** * Encrypt data with key. * * @param v * @param k * @return */ public static int[] encrypt(int[] v, int[] k) { int n = v.length - 1; if (n < 1) { return v; } if (k.length < 4) { int[] key = new int[4]; System.arraycopy(k, 0, key, 0, k.length); k = key; } int z = v[n], y = v[0], delta = 0x9E3779B9, sum = 0, e; int p, q = 6 + 52 / (n + 1); while (q-- > 0) { sum = sum + delta; e = sum >>> 2 & 3; for (p = 0; p < n; p++) { y = v[p + 1]; z = v[p] += (z >>> 5 ^ y << 2) + (y >>> 3 ^ z << 4) ^ (sum ^ y) + (k[p & 3 ^ e] ^ z); } y = v[0]; z = v[n] += (z >>> 5 ^ y << 2) + (y >>> 3 ^ z << 4) ^ (sum ^ y) + (k[p & 3 ^ e] ^ z); } return v; } /** * Decrypt data with key. * * @param v * @param k * @return */ public static int[] decrypt(int[] v, int[] k) { int n = v.length - 1; if (n < 1) { return v; } if (k.length < 4) { int[] key = new int[4]; System.arraycopy(k, 0, key, 0, k.length); k = key; } int z = v[n], y = v[0], delta = 0x9E3779B9, sum, e; int p, q = 6 + 52 / (n + 1); sum = q * delta; while (sum != 0) { e = sum >>> 2 & 3; for (p = n; p > 0; p--) { z = v[p - 1]; y = v[p] -= (z >>> 5 ^ y << 2) + (y >>> 3 ^ z << 4) ^ (sum ^ y) + (k[p & 3 ^ e] ^ z); } z = v[n]; y = v[0] -= (z >>> 5 ^ y << 2) + (y >>> 3 ^ z << 4) ^ (sum ^ y) + (k[p & 3 ^ e] ^ z); sum = sum - delta; } return v; } /** * Convert byte array to int array. * * @param data * @param includeLength * @return */ private static int[] toIntArray(byte[] data, boolean includeLength) { int n = (((data.length & 3) == 0) ? (data.length >>> 2) : ((data.length >>> 2) + 1)); int[] result; if (includeLength) { result = new int[n + 1]; result[n] = data.length; } else { result = new int[n]; } n = data.length; for (int i = 0; i < n; i++) { result[i >>> 2] |= (0x000000ff & data[i]) << ((i & 3) << 3); } return result; } /** * Convert int array to byte array. * * @param data * @param includeLength * @return */ private static byte[] toByteArray(int[] data, boolean includeLength) { int n = data.length << 2; if (includeLength) { int m = data[data.length - 1]; if (m > n) { return null; } else { n = m; } } byte[] result = new byte[n]; for (int i = 0; i < n; i++) { result[i] = (byte) ((data[i >>> 2] >>> ((i & 3) << 3)) & 0xff); } return result; } }